How to calc arc length?
I cannot give you the actual arc length as I do not know the original radius or the original angle. But I can give you relations that will be able to compute it if you know the original radius or the angle Φ in radians. An angle of one radian is equal to an arc the length of one radius. Thus… 100 m = r Φ (where Φ is in radians and r in meters) and L m = ( r + 10 m ) Φ where L = the new arc length in meters Then Φ = 100 / r and Φ = L / ( r + 10 ) Then 100 / r = L / ( r + 10 ) Solving for L (the new arc length) is L = ( 100 ( r + 10 ) ) / r L = ( 100 r + 1000 ) / r or L = ( r + 10 ) Φ Posters: Before you give a definite answer to this question, you must understand that all the information needed to give an actual arc length was not provided in the question. Gator, the question did not state that 100 meters encompassed a circle (you assumed Φ to be 2π). Just understand that as r approaches infinity, r+10 makes very little difference and the arc length at Φ will be almost be the same as
